A rectangle footing $($Length $2\mathrm{.}5m$ Width $1\mathrm{.}5m),$ subjected to a moment of $(90,)$ kNm about an axis parallel to the length in addition to the vertical load $300kN,$ is located at a depth of $1\mathrm{.}6m$ below the ground surface in sand. The ground water level is $0\mathrm{.}4m$ below the ground surface $($see Figure $4).$

Assume for dense sand;